1 Field of the Invention
The present invention relates to a sequential automatic transmission, and more particularly to a sequential automatic transmission which can preferably suppress an impact (shift shock) at the time of performing transmission.
2 Description of Background Art
A shift control device for an automatic transmission for a vehicle-use engine, for example, a shift control device of a plural-clutch-type transmission, is described in JP-A-2004-28117 which includes a shift manipulation mechanism for allowing a driver to give a neutral standby instruction to the transmission. When the neutral standby instruction is given from a shift manipulation mechanism, the shift control device changes over a transmission mechanism which belongs to a rotational power transmission system in which a clutch is released to a neutral state without performing a shift changeover operation.
The shift control device of the automatic transmission described in JP-A-2004-28117 brings the shift gears into a neutral state when the shift manipulation mechanism is in a neutral state. When the shift manipulation mechanism is changed over to a drive position, a shift-up operation corresponding to a vehicle speed is performed from the low-speed gear.
However, a situation may occur in which when a vehicle is not completely stopped on a descending slope or the like, the shift manipulation mechanism is changed over to the drive position from a state in which the shift manipulation mechanism is manipulated in the neutral position. In such a case, the transmission is changed over to the low-speed gear when the vehicle speed assumes a certain state. Thus, there may be a situation in which a large engine brake is generated thus giving a discomfort to a driver. Further, a load applied to clutches is also increased. Accordingly, there exists a task to obtain favorable shift feeling by reducing this engine brake and to decrease the load applied to the clutches.